MECHANOSENSORY PROJECTIONS FROM MOUTH PARTS j ‘ . .

T0 VENTROBASAL THALAMUS m opossum. -

,SQUIRREL MONKEY, Aeoun, CAT AND moon _ .; ' . -

'   - Thesis for the Degree of MS.   3
' MICHiGAN STATE UNIVERSITY
ROCCO A. BOMBARDiERI, Jr.

1971

 

 

 

 

H125.)

L I B R A R Y
Michigan State
University

 

ABSTRACT

momosmsom PROJECTIONS mom
MOUTH PARTS 'ro VENTROBASAL rmuuus IN
opossum, SQUIRREL MONKEY, AGOU‘I'I, on, AND mccoon

By
Rocco A. Bombardieri, Jr.

The mechanosensory projections from mouth parts were

examined in the ventrobasal complex of the thalamus in the

opossum, Didglphig gagggpigligj the squirrel monkey; §gig§£i

sc‘ us: the acouti. W m: th- cat. mu m:
and the raccoon, zxggygg,1312;, Microelectrode recording

techniques were used in acute experiments to determine the
character (;,g, ipsilateral or contralateral) and organisa-
tion of projections from the intraoral surfaces primarily
and secondarily from the perioral surfaces.

In the five species studied the perioral representation
in the thalamus is primarily contralateral. It was shown that
in the opossum the projections from the intraoral surfaces are
essentially completely contralateral. A small ipsilateral
representation was found in the thalamus of the squirrel monkey
and the agouti but the projections are primarily contralateral.
Both the cat and the raccoon show a large ipsilateral represen-
tation and in the case of the raccoon the contralateral
component is greatly reduced. These data are compared to
those of Cabral and Johnson (1971) on the sheep, Qxillggigg,
They reported a large ipsilateral representation from the
perioral surfaces and an essentially completely ipsilateral

representation from the intraoral surfaces.

Rocco A. Bombardieri, Jr.

In the contralateral projections to the ventrobasal
thalamus of the opossum, agouti, and squirrel monkey the
dorsal or maxillary mouth parts project dorsally to the
ventral or mandibular mouth parts. In the cat the intraoral
ipsilateral projections are ventromedial to the contra-
lateral projections. In the raccoon thalamus the teeth
project dorsally to the other mouth parts. No consistent
organization was demonstrated withinrthe projection pattern
of the teeth themselves. Projecting below the teeth is the
palate and below that either the tongue or the incisor pad,
with a tendency for the tongue to project more medially and
the incisor pad more laterally.

In every species studied most of the intraoral
projections are from the teeth. In the agouti only the
incisors were seen to project to the ventrobasal complex.
Every subject species also had projections to the thalamus
from the dorsal surface of the tongue. Projections were
seen from the gum in the opossum; from the mucous membrane
surrounding the lower incisors in the agouti; from the
ventral surface of the tongue in the cat; and from the check,
the rostral throat area and the pad just posterior to the
upper incisors in the raccoon.

It is suggested that the variation in character of the
projections to the ventrobasal complex reflects the major
subdivisions (cohorts) of the class Mammalia as defined
by Simpson (1945). An alternate hypothesis is suggested in

which the variations represent specialisations of groups

Rocco A. Bombardieri, Jr.

lower than cohort.

MECHANOSENSORY PROJECTIONS FROM
MOUTH PARTS TO VENTROBASAL THALAMUS IN
opossum, SQUIRREL MONKEY, AGOUTI, CAT AND RACCOON

"\- ‘ By
Rocco A3 Bombardieri, Jr.

A THESIS
Submitted to
MICHIGAN STATE UNIVERSITY
In partial fulfillment of the requirements
for the degree of
MASTER OF SCIENCE
Department of Zoology
1971

ACKNOWLEDGEMENTS

I gratefully extend my appreciation to: Dr. John I.
Johnson, Jr. who served as chairman of the research committee
and who provided assistance and encouragement throughout the
course of this work; Drs. Robert Raisler and Rollin Baker
who served as committee members and assisted in the prepara-
tion of the manuscript; Dr. Richard V. Dukelow for
assistance in the procurement and handling of squirrel
monkeys; Dr. Gilberto B. Campos for assistance in analysing
the agouti data; Andrew Harton, Grace Kim, Emeline Haight,
and Kristi Dege for their work in histological preparation
of the tissue; John R. Haight for maintenance of the
electronic equipment; Paul Herron for photographic assistance;
and Joan Bernstein and Dan Hoekema for assistance in the
collection of data.

This research was supported by NIH training grant

GM 01751 and research grant NS 05982.

ii

TABLE OF CONTENTS

LIST OF TABLES
LIST OF FIGURES

Introduction
Subjects and Preparation
Recording Apparatus
Response Criteria
Mapping Procedures
Tissue Preparation

Results
Overview
Opossum
Squirrel Monkey
Agouti
Cat
Raccoon

Discussion

Bibliography
General References

iii

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"30““

19
24

36
42

62

iv

19

55
59

LIST OF TABLES

TABLE

1 Subjects and Treatments

2 Summary of Character of Responses

3 Intraoral Structures Eliciting a Response
in Vb.

4 List of Abbreviations

iv

PAGE
12
20

22
25

FIGURE
1.

9.

10.

11.

12.

13.

LIST OF FIGURES

Diagrammatic representation of
mechanoreceptor projections in the
ventrobasal thalamus of sheep (Cabral
and Johnson, 1971) and raccoons
(Velker and Johnson, 1965)

Ma'or extant Mammalian groups as
de ined by Simpson (1945).

Samples of criterion responses, unit
clusters, in the five species studied.

Projection pattern in a coronal row of
punctures in opossum 553.

Projection pattern in a coronal row of
punctures in opossum 556.

Projection pattern in a coronal row of
punctures in squirrel monkey 562.

Projection pattern in a coronal row of
punctures in squirrel monkey 563.

Pattern of projections in a coronal row
of punctures in agouti 593.

Pattern of projections in a coronal row
of punctures in agouti 591.

Pattern of projections in a corOnal row of
punctures in cat 560.

Pattern of projections in a coronal row of
punctures in cat 557.

Pattern of projections in a rasagittal
row of punctures in raccoon 65.

Pattern of projections in a coronal row
of punctures in raccoon 564.

PAGE

10

15

26

28

32

34

38

4O

45

47

51

53

INTRODUCTION

The ventrobasal complex of the mammalian thalamus (vb)
represents an area of second order synapses of the medial
lemniscal system and displays a somatotopic organisation
of mechanosensory projections from the body surface (Rose
and Mountcastle, 1959). The pattern of projections from
body parts in vb forms a figure, often with areal distortions,
which, in coronal section, depicts a lateral view of the
body surface. Figure 1 demonstrates the representation
pattern in the raccoon and in the sheep. The caudal body
parts are represented laterally and the rostral parts are
represented medially. The axial body parts are represented
dorsally and the more distal parts ventrally in the thalamus.
Note also the large forepaw in the schematic raccoon in
Figure 1. This indicates the large amount of thalamic
tissue devoted to projections from the forepaw in the
raccoon. In the sheep there is a large face and intraoral
projection area. In most animals studied the projections
from the trunk and limbs are all from the contralateral (cl)
side and the projections from the head and mouth are from
either the cl side, or the ipsilateral (ips) side, or from
both sides of the body. It should be noted that the above
description is generalised and each animal displays some
specialisations.

One portion of vb which is the subject of much confusion
in the literature is the most medial region, 1.1,, that

region receiving projections from the perioral and the
1

Figure 1. Diagrammatic representation of mechanoreceptor
projections in the ventrobasal thalamus of sheep (Cabral
and Johnson, 1971) and raccoons (Velker and Johnson, 1965).

Top: Diagram to show location of this region in the brains.

Center: Outline diagram of coronal section through the
thalamus showing approximate locations of projections from
ipsilateral and contralateral body parts.

Bottom: A pictorial representation of these projections,
which for raccoons anticipates data from more caudal planes.
A separate ipsilateral representation of tissues inside the
mouth occurs in both animals, with tongue projections ventral-
most; just dorsal to these are projections from the palate
and upper teeth; .next dorsal are projections from the lower
gums and teeth. In addition, in sheep there is a massive
projection from the ipsilateral face, largely from the nose,
ventralmost, the hairy protions of skin between the nose and
lips dorsal to these glabrous pipillae of upper and lower
lips next, and dorsai-most, from hairy skin between lips and
chénS (Figure and caption from Johnson, Hatton, and Rubel,
19 9 .

 

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CONT RALAT ERAL

   

Figure 1

4
intraoral body surfaces. Cabral and Johnson (1971) studied
the mechanoreceptive projections in vb in sheep, Q: g agigg,
and discovered three particularly interesting and unusual
features of this somatotopic organisation:

1. There is a greatly enlarged head and face area
represented in the thalamus. 2. The projections from ips
body parts dominate vb in sheep to a greater extent than

in any animal studied so far. 3. In the most medial areas
of the thalamus, where there are projections from the ips
face and intraoral regions, the somatotopic organisation is
quite unusual. In the cl representation in most mammals
studied, as in sheep, the projections from the maxillary
lips and the surrounding hairy skin are dorsal to those
from the corresponding mandibular regions. In the ips
projection areas of the sheep this situation is reversed.

A similar situation exists with regard to projections from
the interior of the mouth. Going through the thalamus in a
dorsal-ventral direction Cabral and Johnson (1971) found
ips lower teeth, upper teeth, and finally, most ventrally,
tongue (see Figure 1).

The organization of vb was examined by Mountcastle and
Henneman (1949) in the cat. They found both cl and ips
responses from the face region, but the face responses were
predominantly cl. The organization of the cl responses
resembled that of the head itself,,1rg., the maxillary
projections were dorsal to the mandibular. The ips face

responses were few and it is unclear whether they are

5
organised as are the cl responses or are inverted as in the
sheep ips area. The responses from the interior of the
mouth were primarily ips and here again it is unclear as
to how they are organised. Rose and Mountcastle (1952)
again studied the cat thalamus but their data do not define
the organisation of the ips projections from the face or
mouth.

The thalamus of the macaque monkey was examined by
Mountcastle and Henneman (1952). Again both ips and cl face
and mouth representation was located. The somatotopic
organisation in the regions receiving ips projections was
not examined in detail fine enough to determine exactly the
pattern of organisation.

In the rabbit thalamus the representation of the face
and mouth is quite large (Rose and Mountcastle, 1952). The
most striking information that may be inferred from the
study on the rabbit is that the projections from the
maxillary face are much greater than those from the mandibular
face. It seems that most of the face is represented from
the cl side. There is apparently considerable representa-
tion from the perioral and intraoral surfaces but the exact
nature of the somatotopic organization was not described.

Emmers (1965) examined the albino rat thalamus and
reported an organisational pattern which has been found in

no other mammalian thalamus. He found two complete series

6
of projections which he calls SI and $11 to correspond to
the SI and SII receiving areas in the cortex which have been
seen in many mammals (Noolsey, 1958). Emmers found that
the projections in the area he termed SI were cl and those
in the area he termed 811 were bilateral. His results are
very unusual for two reasons: 1. The discovery of an SI and
an $11 thalamus is a unique finding and 2. In his SI area,
which includes the most medial area of vb, he found no ips
representation. In every other animal studied so far there
has been at least some ips representation reported in the
most medial part of the complex.

The raccoon, Egggygn,lgtgg, thalamus was examined by
Welker and Johnson (1965) and they found some ips representation
of the face, mouth, and tongue but they did not examine in
detail the organisation of these ips responses.

Pubols and Pubbls (1966) examined the thalamus of the
opossum, nigglphig gagggpiglig, and found some ips head
representation. They did not, however, describe the organisa-
tion of these projections. They did not find any responses
from the interior of the mouth because, apparently, they
didn't look for them.

The reported face and mouth representation in the
spider monkey, Atglgg, thalamus (Pubols, 1968) is consider-
ably less extensive than in either the macaque, nagggg,
(Mountcastle and Henneman, 1952) or the squirrel monkey,

m m, (Blomquist, Benjamin, and Emmers, 1962).

Only a few ips responses were found but the author admits

7
that the mapping procedures used may have made the localisation
of ips responses unlikely.
Thus, researchers have

electrophysiologically mapped the thalami of the sheep,

9:11. amiss: the cat. 22m. seam: the albino rat. mm
W: the reccoon. 2mm lens; the ope-ewe.

W W: the neceque monkey. m end the
spider monkey,_Aiglgg. The ips projection area in the

thalamus of sheep is large and its organisation is inverted
when compared to the organisation of the cl projection areas
seen in other animals studied. Cats seem to have an ips
component in vb but its organisation is unclear. Rabbits
have a large face and mouth representation but the somato-
topic organisation has not been described. The data from
the rat vb are very unusual and therefore of little help in
the elucidation of any general organisational pattern which
may exist in the mammalian vb. In both the raccoon and the
opossum, ips responses were located by previous researchers
but their organisation was not described. Two monkeys, the
macaque and the spider monkey, have been studied but in
both instances the ips response area was not mapped.

From the above literature review it should be clear
that little attention has been paid to the mechanosensory
projections from the mouth parts to vb. It should also be
clear that the relative proportions of ips vs cl projections
from the mouth parts have not been adequately elucidated for

the mammals which have been studied with the exception of

8
the work on sheep (Cabral and Johnson, 1971). Again with
that exception, the detailed organisation of the mouth parts'
projections has not been described. In this study I have
analysed by means of electrophysiological recording, and
described the mechanosensory projections from the mouth parts
to vb in five mammals, the common opossum, Didslnhis

W: the squirrel monkey. my. sums: the agouti.
pagypgggta,aguti; the domestic cat,.zglig.ggtng; and the

raccoon, 2:33y33,;012;.

The rationale for choosing the above animals deserves
some mention. The opossum was used because it was available
in the Laboratory of Comparative Neurology where this
research was conducted and because it represents the infra-
class Metatheria, the pouched mammals (Simpson, 1945). The
other mammals studied are members of the infraclass Eutheria,
the placental mammals. The squirrel monkey was chosen on
the basis of its availability and represents cohort Uhguiculata
and order Primates. Also, it is known to have at least some
ipsilateral tongue projections (Blomquist, Benjamin, and
Emmers, 1962). The agouti was chosen to represent the cohort
Glires, order Rodentia. Compared to common rodents it is a
large animal with a large thalamus which permits more
detailed mapping. The cat and the raccoon were chosen
because they are common animals used in electrophysiological
research and the data collected would therefore be especially
valuable because they add to a growing fund of knowledge on

the sensory systems of these animals. Both these animals

9
are members of the cohort Ferungulata, superorder Ferea,
and order Carnivora. It should be noted here that the sheep
is a member of cohort Ferungulata, superorder Paraxonia, and
order Artiodactyla.

In my final comparisons in which I include the data of
Cabral and Johnson (1971) on sheep, I will compare the two
infraclasses, Metatheria and Eutheria, within the subclass
Theria. Within the infraclass Eutheria I will compare
"representatives" of three cohorts, Unguiculata as represen-
ted by the squirrel monkey, Glires, as represented by the
agouti, and Ferungulata as represented by the cat, raccoon,
and sheep.

It should be noted here that comparison of animals
related as distantly as even my most closely related subjects
is a somewhat hasardous task. This study describes the pro-
portions of ips versus cl projections from the mouth parts
to vb in various mammals who are members of the major groups
(cohorts) of mammals as defined by Simpson (1945) (see Figure
2) and presents detailed projection patterns of the mouth
parts for each animal. These are compared and discussed in
light of what is known of mammalian evolution. In other
words this study is designed to learn how much of the mouth
projections are to the ips vb versus the cl thalamus and to
learn if the ips somatotopic organisation seen in sheep is
a specialisation of sheep of is representative of a
general mammalian pattern which is particularly obvious in

sheep due to the large amount of thalamic tissue involved.

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11
METHODS

mmw

Table 1 describes the source of each animal, number of
animals used, and drugs administered to each subject species.

On the day preceding each experiment the animal was
deprived of food. The anesthetised subject was shaved on
the top of the head and in the throat region. The trachea
was exposed, opened, and a cannula inserted to permit
immediate mechanical respiratory assistance as required.
The skull was exposed, cleaned of all overlying skin and
muscle, and secured to a head holder by means of screws
fastened to each sygomatic arch. The screws were secured
to the head holder bars by means of dental acrylic. Another
screw was fastened to the occipital ridge and secured to the
headholder by means of another bar and dental acrylic. The
brain was then exPosed by removing the skull and a dam of
dental acrylic was built on the skull around the brain. The
dura was cut and reflected and the exposed brain protected
with warmed mineral oil for the duration of the experiment.
The exposed cortical surface was photographed and an enlarged
print made on which the position of the electrode was noted
during the experiment.

Frequently, throughout the experiment, a warmed solution
of normal saline (0.9%NaCl) was applied to the buccal cavity

in order to prevent the tissue from drying.

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14
WW

Tungsten microelectrodes were manufactured before the
experiment using the method of Hubel (1957), except that they
were insulated with glass as described by Baldwin, Frank,
and Lettvin (1965), and the glass on the tip of the electrode
was etched with hydrofluoric acid so that 15 to 50 microns
of the tip was exposed.

For recording, the microelectrode was clamped in a
shielded holder, and shielded leads led from it to a
Tektronix 122 preamplifier. Signals here were amplified X
1000 and fed into an audio monitor and an oscilloscope.

From the oscilloscope they were fed into a Magnecord 1028
magnetic tape recorder for storage, and when appropriate for
visual reproduction, they were subsequently played from the
tape through the oscilloscope and were photographed.
Rggpgnse Critggia

The criterion of a true response was a cluster of unit
discharges which could regularly be activated by careful
mechanical stimulation of localized body tissues (Figure 3).
During the experiment a response was usually identifiable by
the audio signal and in cases of doubt a close examination
of the visual record confirmed the presence or absence of a
response. Normally the units of a positive response were
recorded at an amplitude of at least 50 microvolts with an
average baseline amplitude of 10-30 microvolts.

A second type of response, termed a low signal/noise

response (low s/n), was recorded. A low s/n consisted of a

15

RESPONSE SAMPLES

Animal Response 50uv Receptive Field Character

Opossum 554 CI
Squirrel Monkey

563 CI
Agouti 593 CI
Cal 557 CI
Raccoon 565 Ips

 

_
40 msec

Figure 3. Samples of criterion responses,
unit clusters, in the five species studied..

16
group of units with amplitudes less than 50 microvolts.
Low s/n responses are not included in the data tabulations
but in instances where it was felt they would be useful in
interpretation they were included in the figures and at all
times distinguished from criterion responses.
Mapping Procedures

Mapping consisted of a regular series of steps:

1. The microelectrode was introduced into the medial
thalamus in a series of regularly spaced punctures, usually
in rows 3/4 - 1 mm apart, with punctures within a row 1/4
to 1/2 mm apart. Because of the small amount of thalamic
tissue involved it was often necessary to make several
punctures before vb was located. In those cases, therefore,
.punctures were not always as regularly spaced as would be
desired.

2. The electrode was moved quickly through the tissue
overlying the thalamus and then more slowly through the
thalamus itself while the body, face, and intraoral surfaces
were mechanically stimulated. For gross localization the
experimenter used his hand to stimulate the animal's body
and for fine localization a short wooden rod or a small
piece of plastic ("Intramedic") tubing was used as a stimulus.
When a response was encountered the peripheral receptive
field was delineated. The mouth was mapped in particularly
fine detail. The experiment was continued until either the
animal died, the experimenter fatigued, or no mouth responses

were located anteriorly, posteriorly, medially, or laterally

17
to that area which did respond to stimulation of the
intraoral surfaces.

3. For each response point the response activity was
recorded on magnetic tape, along with a verbal description
of the electrode coordinates and the minimal activating
peripheral field on a synchronized second tape channel. A
verbal description was also summarized in a written protocol,
and the peripheral field was drawn on a photograph of the
relevant part of the animal's body. A new response point or
locus was recorded: a. when a receptive field was first
localized; or b. when the receptive field changed signifi-
cantly in size or location as the electrode was moved
through the thalamus.

4. For marking the location of responding units of
special interest or for help in later identification of
tracks, marking microlesions were made by passing 4O
microamp electric current through the recording electrode
tip as anode. In those cases when the ammeter indicated
that little current had passed through the electrode the
polarity of the electrode was reversed and a brief pulse
of current was passed through the recording electrode tip
as cathode.

Tigsue Pr ea a ‘on

At the conclusion of each experiment, the plane of
electrode punctures was marked by inserting pieces of
hypodermic tybing at the boundaries of the investigated

area, using the electrode holder and the micromanipulator.

18

The animal was then perfused through the heart with normal
saline followed by a mixture of 10% formalin and normal
saline. After 24 hours the brain was removed and photo-
graphed, and a block of tissue containing the electrode
punctures was trimmed by cutting along the plane of the
inserted tubing. The tissue was dehydrated, embedded in
celloidin, and sectioned at 25 microns in the plane of rows
of electrode punctures. Alternate sections were stained
with thionin for cell bodies, and with hematoxylin for
myelinated fibers. Sections were examined microscopically

to identify punctures and to localize the marking lesions.

RESULTS
Overview

In all species studied the projections from the face to
vb are primarily cl (see Table 2). The intraoral projections,
on the other hand, vary among the species studied in the
percentages of data points which include ips responses and in
the percentages of data points which include cl responses
(see Table 2). The opossum intrsoral projections are entirely
cl while the squirrel monkey and the agouti have small ips
components and large cl components. The cat and the raccoon
have large ips components and in the case of the raccoon the
Cl component is reduced. Table 2 includes data from Cabral
and Johnson (1971) which will be discussed later.

In the ventrobasal thalamus of the opossum, agouti, and
squirrel monkey the projections of the maxillary mouth parts
are dorsal to those of the mandibular mouth parts. In the
cat the ips projections are ventromedial to the cl projections.
Tn the raccoon thalamus the teeth projections are dorsal to
those of other month parts. No consistent organizational
pattern was demonstrated within the teeth projections
themselves. Below the teeth projections are those of the
palate: and below these either projections from the tongue
or from the incisor pad. There is a tendency for the tongue
to project more medially and incisor pad more laterally.

Following are detailed presentations of the results for
individual species. The order of presentation reflects
Simpson's (1945) classification of mammals (see Figure 2)

19

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21
because the data will later be discussed in light of that
classification.

Table 3 summarizes the intraoral structures from which
positive responses were elicited in each of the animals
studied. In every case most of the projections were from
the teeth. The agouti was unusual in that the incisors were
the only teeth from which responses were elicited. Projections
from the palate were seen in all species except the agouti
and the squirrel monkey. Positive responses were elicited
by stimulation of the dorsal surface of the tongue in all
species studied.

Oposgum

In the three opossums studied five thalami were
explored. In specimen 553 the punctures were done in a
vertical plane. It was evident from that experiment that
the most medial vertical punctures possible without either
piercing or removing the superior sagittal sinus would not
reach the most medial areas of vb. For that reason the
electrode punctures in the subsequent opossum experiments
(554 and 556) were introduced lateral to vb and directed at
an angle toward the midline. One interesting result of this
procedure was that in several instances the electrode
crossed the midline and data were recorded in vb on the side
cl to the electrode entry. It should be noted that all
responses will be referred to the side from which the data
were actually recorded (as determined by localization of the

electrode tracks in the stained sections) and not necessarily

22

 

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23
from the side where the electrode first pierced the brain.

A total of 46 punctures were made in the five thalami and
23 (50%) of these yielded data. Ten of these punctures
included data from the body surface excluding face, 17 from
the face and perioral surfaces and 11 from the intraoral
surfaces. Intraoral responses were localized from the teeth,
tongue and palate regions.

In the 23 punctures which included data 90 response
points were localized. Sixteen of these included responses
from the body surfaces, 49 from the face, jaw, and perioral
surfaces, and 26 from the intraoral surfaces.

or the 26 intraoral responses 25 (96%) included teeth, and
3 (12%) included responses from the palate. There was also
one point which responded to stimulation of the very
small area of tissue between the upper incisors and the
rhinarium. This area may best be termed gum.

Of the 25 data points responding to stimulation of the
teeth 5 (20%) responded to stimulation of the upper teeth
to the exclusion of the lower, 9 (36%) responded to stimula-
tion of the lower teeth to the exclusion of the upper and
11 (44%) responded at the same locus to stimulation of both
the upper and lower teeth.

The character of the projections to vb in opossums is
evident from this study. Of the 90 data points observed
39 (90%) were completely cl. At one locus a bilateral
response from both the cl and ips anterior lower lip was

Obtained e

24

The somatotopic organization of the medial parts of vb
is also evident. Both the perioral and intraoral projections
are organised in much the same way as are the cl body
projections to the thalamus in other animals studied, includ-
ing the opossum (Pubols and Pubols, 1966). In other words
the more dorsal body elements are represented dorsally in
the thalamus and the more ventral body elements are represen-
ted in the ventral region of the complex. Also, the most
medial areas of the complex are devoted to representation
from the interior of the mouth. These details are best seen
in Figures 4 and 5.

The data collected demonstrate that there are projections
from the intraoral surfaces which include teeth, tongue, and
palate, and from the perioral surfaces. The overwhelming
majority of the projections are from the cl side and these
are organized in much the same way the cl projections from
the body surfaces project to the dorsal area of the complex
and ventral surfaces project to the ventral area of the
complex. It is also seen that the most medial projections
are from the mouth parts.

Sguirrel Monkey

In the two squirrel monkeys studied three thalami were
explored. The electrode was moved in a vertical plane, ;.2.
not tilted, during both experiments.

Thirty-six punctures were made and fifteen (42%) of

these yielded data. Four punctures included responses from

25
Table 4
LIST OF ABBREVIATIONS

A.. Abbreviations used in Figures 4-13. Abbreviations of
brain structures after Oswaldo-Cruz and Rocha-Miranda (1968).

A anterior

cha commissura habenulae

ci capsula interna

fx (columna)fornicis

GLD nucleus corporis geniculati lateralis dorsalis
GLV nucleus corporis geniculati lateralis ventralis
GM nucleus corporis geniculati medialis
HM nucleus medialis habenulae

IMD nucleus intermedialis dorsalis

L lateral

M medial

Mm nucleus mamillaris; pars medialis

mm millimeter

mth fasciculus mamillothalamicus

nIII nervus oculomotorius

P posterior

ped pedunculus cerebri

rfl fasciculus retroflexus

Rt nucleus reticularis thalami

SN substantia nigra

STh nucleus subthalamicus

tro tractus opticus

VM nucleus ventralis thalami medialis
xVB nuclei ventralis thalami basalis

ZI zona incerta

B. Abbreviations used in the body of the thesis.

cl contralateral
ips ipsilateral
vb ventrobasal complex of the thalamus

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30
the body surface excluding face, eight included responses from
the face, jaw, and perioral surfaces, and six included
responses from the interior of the mouth. The only intraoral
surfaces from which responses were elicited in the squirrel
monkey were the teeth and the dorsal surface of the tongue.

In the fifteen punctures which included data 57 data
points were localized. Thirteen of these included responses
from the body parts excluding face, 24 included responses
from the face, jaw, and perioral surfaces, and 20 responded
to stimulation of the intraoral surfaces.

Twelve (60%) of the 20 mouth data points responded to
stimulation of the teeth and 8 (40%) responded to stimulation
of the tongue. In these experiments there were no data loci
which responded to both teeth and tongue.

0f the 12 data points responding to stimulation of the
teeth 7 responded to stimulation of the upper teeth to the
exclusion of the lower teeth and five responded to stimula-
tion of the lower teeth to the exclusion of the upper. There
were no data points responding to both upper and lower teeth
simultaneously.

In the squirrel monkey, as in the cat, both cl and ips
projections are seen in vb. All of the thirteen body respon-
ses were cl and all of the 24 data points from the face
included projections from the cl surfaces. One of these
data points responded to stimulation of a small area on the
middle of the rostral nose and therefore must be said to

include both a cl and an ips component. Of the 20 data

31
points responding to stimulation of the intraoral surfaces
17 (85%) included responses from the cl surfaces and 7 (33%)
included responses from the ips surfaces. Included in the ips
responses were the tip of the tongue, the incisors, the canine,
and the molars.

The cl intraoral projections are seen in the lateral
edge of the mouth projection area (Figure 5). The most
dorsal of these projections are from the maxillary teeth,
followed ventrally by projections from the mandibular teeth
and finally most ventrally are the projections from the
tongue. More medially in the complex are found the ips and
bilateral loci (Figure 6). (In this very small medial mouth
projection area the teeth, both cl and ips, project dorsally
and the tongue, which again may include ips and/or cl compon-
ents, projects ventrally (Figures 6 and 7).

In these squirrel monkey experiments the face projected
almost exclusively to the c1 thalamus while the interior of
the mouth projected to both the c1 and ips sides. The c1
mouth projections are organized as are most cl projections
to the thalamus. The dorsal body parts project to the dorsal
part of the complex and the ventral parts project to the
ventral part of the complex. In the most medial projection
area both c1 and bilateral responses are seen and in this
area the teeth project dorsally to the tongue. There are
too few responses in this region to define an organizational

pattern among them.

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36
Agogti

Six thalami were explored in four agoutis but only the
data from three thalami in three agoutis will be examined here.
In one subject, 592, all electrode tracks were seen, upon
examination of the prepared sections, to be lateral to the
thalamus in the region of the reticular nucleus and the
internal capsule. In specimen 593 the one data point that
was found in the left thalamus was also localised lateral to
vb. The above mentioned data may have been recorded from
post-synaptic fibers but will not be included in the
tabulations. In all experiments the electrode was moved in
a vertical plane, ;,g. not tilted.

A total of 60 punctures were made and 37 (62%) yielded
data. Eleven punctures included data from the body surface
excluding face. Twenty-five puncutres included data from
the face, jaw, and perioral surfaces, and eleven included
intraoral responses. In the agouti there are two folds of
hairy skin which extend down from the face, fold into the
mouth, and meet each other. The responses from the external
surface of this hairy skin are considered perioral. Intra-
oral responses were elicited from the incisors, the tongue,
the mucous membrane around the lower incisors, and from the
inside of the lip.

Ninety-nine data points were localized and examined of
which 23 included responses from the body surface excluding
the face, 56 included responses from'the face, jaw, and
perioral surfaces, and 21 included responses from intraoral

surfaces.

37

Thirteen (62%) of the 21 intraoral data points included
incisor responses, 4 (19%) included responses from the dorsal
surface of the tongue, 3 (14%) included responses from the
inside of the lip, and 2 (10%) included responses from the
intraoral surfaces.

Four (31%) of the 13 incisor data points responded to
stimulation of the upper incisors to the exclusion of the
lower, 8 (62%) responded to stimulation of the lower incisors
to the exclusion of the upper and 1 (8%) responded to stimula-
tion of both upper and lower incisors.

The agouti experiments demonstrated an almost entirely
cl representation in vb. All of the responses from the body
and the face which were recorded in the nucleus were entirely
cl. In the left thalamus of 593, however, the one response
mentioned earlier was an ips response from the hairy skin
which folds inside the mouth. This response was localised
outside the nucleus. Its significance is unclear. All 21
of the intraoral responses included a c1 component and 3 (1¢%)
of these also included an ips component. In those cases
both incisors responded together and it was impossible to
determine if the ips tooth was responding directly or merely
stimulating the c1 tooth.

These data demonstrate a clear organisational pattern
for both the intraoral and perioral responses. The body
projections are lateral to the projections from the face,
jaw, and perioral surfaces which are, in turn, lateral to

the projections from the intraoral surfaces (Figures 8 and 9).

 

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42
In the dorsal-ventral direction the organization of the
projections is as would be expected in any c1 thalamic
projection pattern. The dorsal or maxillary face or tooth
project dorsally to tho corresponding ventral or mandibular
surfaces (Figure 9). In those punctures which included
tongue the tongue projected most ventrally (Figure 9).

These experiments have demonstrated that the thalmaic
projections in the agouti are primarily cl and organised as
other cl projection patterns are; 1.1. dorsal body parts
projecting dorsally, ventral body parts projecting ventrally,
and rostral parts projecting medially. One unusual feature
of the representation is that the only teeth which were
found to project to vb were the incisors.

931

In the five cats on which experiments were performed 7
thalami were explored. In all experiments except one the
electrode was moved down to the thalamus in vertical plane.
In animal 561 the subject's head was tilted in the headholder
and therefore the electrode was introduced lateral to vb and
moved at an angle toward the midline.

One hundred and forty punctures were made and 51 (36.4%)
of these yielded data. Twenty-two punctures included data
from the body surfaces excluding face, 22 yielded data from
the face, jaw, and perioral regions, and 19 yielded data from
the intraoral surfaces. The intraoral surfaces from which
responses were elicited included teeth, palate, dorsal surface

of the tongue, and the ventral surface of the tongue and its

43
attachment to the floor of the mouth.

In the 51 punctures which included data 125 response
points were localised. Forty-three included responses from
the body surface, 57 included responses from the face, jaw,
and perioral surfaces, and 39 included responses from the
intraoral surfaces.

Of the 39 intraoral response loci 36 (95%) responded to
stimulation of the teeth, 7 (19%) responded to stimulation
of the palate, 4 (11%) responded to stimulation of the dorsal
surface of the tongue and 2(5%) responded to stimulation of
the tissues on the ventral surface of the tongue and the
floor of the mouth.

Of the 36 loci responding to stimulation of the teeth
10 (27%) responded to stimulation of the upper teeth to the
exclusion of the lower: 13(36%) responded to stimulation
of both upper and lower teeth.

In the cat both cl and ips projections are seen in vb.

All 43 data points responding to stimulation of the general
body surface were, as expected, cl, while of the 57 data
points responding to stimulation of the face, jaw, and
perioral surfaces 53 (93%) included responses from the
cl side and 5 (9%) included responses from the ips side.
Of the 39 loci responding to stimulation of the intraoral
surfaces 27 (69%) included responses from the cl side and
20 (51%) included responses from the ips side.

Because of the small size of vb receiving projections

from inside the mouth it is impossible to state, with one

44
exception, exactly what the somatotopic organisation is. In
some instances the lower teeth project ventrally in the
thalamus, while in other instances the upper teeth are seen
to lie ventral to the lower teeth. One pattern which does
appear is for the ips responses to be located ventro-medially
to the c1 responses (Figures 10 and 11).

These experiments demonstrate that the cat has both cl
and ips projections from the face and mouth to vb and that
the ips projections are ventromedial to the cl projections.
These experiments have not, however, demonstrated the
somatotopic organisation of the projections to the medial
areas of vb.

m

Three thalami were explored in three raccoons. In all
experiments the electrode was moved in a vertical plane,
_i_.;. not tilted.

Sixty-eight punctures were made and 48 (71%) of these
yielded data. Two punctures included data from the body
surface excluding the face, 21 included data from the face,
jaw, and perioral surfaces and 40 included data from the
interior of the mouth. The intraoral surfaces from which
responses were elicited were the teeth, the dorsal surface
of the tongue, the pad just posterior to the upper incisors,

the palate, the cheek, and the rostral throat area.

 

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49

In the 48 punctures which included data, 119 data points
were localised. Only 2 of those included responses from the
body excluding the face. Thirty-four included responses
from the face, jaw, and perioral surfaces and 99 included
responses from the intraoral surfaces.

Fifty-nine (60%) of the 99 intraoral data points
responded to stimulation of the teeth. Thirty (30%)
responded to stimulation of the tongue, nineteen (19%)
responded to stimulation of the pad just posterior to the
upper incosors. Eleven (11%) responded to stimulation of
the palate. In addition two data points responded to
stimulation of the cheek and one responded to stimulation
of the rostral throat area.

Of the 59 data points responding to stimulation of the
teeth 30 (51%) responded to stimulation of the upper teeth
to the exclusion of the lower teeth, 20 (34%) responded to
stimulation of the lower teeth to the exclusion of the
upper teeth and 9 (1%%) responded to stimulation of both
upper and lower teeth.

Again in the raccoon both cl and ips projections are
seen innfb. Both data points which responded to stimulation
of the body were from the cl side. Thirty-three (97%) of
the 34 face data points included responses from the cl side
and 2 (6%) included responses from the ips side. Thirty
(30%) of the 99 mouth data points included responses from
the cl side and 88 (89%) responded to stimulation of the
ips side.

50

- The organisation of the projections from the interior
of the mouth in the raccoon is so complex that only the few
tendencies which are most obvious will be noted. The cl
_projections are scattered among the ips projections and
consist mainly of teeth projections. They are often
associated with ips projections and in those cases the ips
responses were generally stronger. In several instances
all lower teeth, both ips and cl, responded at one data
locus (see locus 12B Figure 12). The cl teeth responses
were too scattered to demonstrate a clear organisational
pattern. The ips responses from the teeth did not demon-
strate a consistent dorsal-ventral organisational pattern
within themselves but did consistently project dorsally to
the other mouth components which were primarily tongue,
palate, and incisor pad (Figure 12). There were too few
punctures in which upper and lower teeth were represented
sequentially, and these punctures showed too much varia-
bility to make a conclusion about dorsal-ventral organisation.
Represented below the tooth was the palate and below that
either the tongue or the incisor pad. There is a tendency
for the tongue to project more medially and the incisor pad
more laterally. (see Figures 12 and 13).

The raccoon vb receives both cl and ips projections
from the body parts. The body and face are represented
almost entirely on the cl side and the mouth is represented
on both the cl and ips sides with the ips projections
dominant. The organisation of the intraoral projections is

complex and unclear except for the tendencies mentioned earlier.

 

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DISCUSSION

The differences in character of intraoral projections
(see Table 2) are systematic when examined in light of
Simpson's (1945) classification of mammals (Figure 2). The
opossum, a member of infraclass Metatheria, is at one end
of Simpson's (1945) "evolutionary scale". It displays a cl
projection pattern from the mouth parts to vb. The cat,
raccoon, and sheep are all eutherians and members of the
cohort Ferungulata which ranks at the other end of Simpson's
(1945) classification. They all display a very large and,
in the case of the raccoon and sheep, predominantly ips
projection pattern from the mouth parts. The squirrel
monkey and agouti who represent respectively cohort
Unguiculata and Glires show an intermediate condition. The
mouth parts project primarily to the cl side with some ips
projections. Both cohort Unguiculata and Glires occupy an
intermediate position in Simpson's (1945) classification.
Moving "up the evolutionary ladder" or out the "evolutionary
limb", therefore, there is a tendency toward increasing ips
projections to vb.

Further evidence for the above hypothesis comes from
a series of electrophysiological studies on the first
somatic sensory area (SI) of the cortex. Efferent project-
ions from vb have been shown to project to 81 (Clark and
Powell, 1953, Pubols, 1968, and Walker and Johnson, 1965).

It is,thorefore, reasonable to infer information about the

55

 

II! II

56
projections to vb by examining the projections upon the
cortex. Electrophysiological mapping studies of the
cerebral cortex support the hypothesis that variation in
the character of projections to vb is systematic.

Lende (1964) studied the echidna (Igghyglglgng
2&3125131) and found considerable head and tongue project-
ions to the cortex which were all cl. The echidna is a
member of subclass Protheria, order Honotremata (Figure 2).
Lende and Sadler (1967) studied the hedgehog (fixingggng)
and reported a completely cl cortical representation pattern
The hedgehog is a member of infraclass Eutheria, cohort
Unguiculata, order Insectivora. Lende (1970) examined the
tree shrew (ggpaig) and again found only cl projections.

The tree shrew is an insectivore-like primate, cohort
Unguiculata, order Primates. In their study of the spider
monkey (51:13:) cortex Pubols and Pubols (1971) found only
two loci with ips intraoral data in 420 responding punctures.
The spider monkey is a member of cohort Unguiculata, order
Primates. The porcupine (EI£IEIIEB.§RZIIIHI) was studied by
Lende and Woolsey (1956) and again only c1 projections were
seen in SI. The porcupine is a member of cohortCEIires,
order Rodentia. Voolsey and Wang (1945) studied the rabbit
and reported cl and ips face projections but did not report
the relative proportions of each. The rabbit is a member of
cohort Glires, order Lagomorpha. Adrian (1943) reported
completely ips projections from the perioral surfaces in

the sheep and the goat and completely cl projections in the

57

pig and the horse. Woolsey and Fairman (1946) found both
ips and cl projections in the sheep and pig. They also
found ips and cl representation from the face in the dog
and the cat. Pinto-Hamuy, Bromiley, and Woolsey (1956)
studied the dog and reported that the palate, teeth, and
lips are represented on the ips side. The sheep, goat, and
pig are all members of cohort Ferungulata, order Artiodactyla.
The horse is a member of cohort Ferungulata, order
Perissodactyla and the cat and dog are members of cohort
Ferungulata, order Carnivora.

These studies are almost completely consistent with
the hypothesis put forward; $.2, more ”advanced" mammalian
groups show a tendency toward a higher degree of ips repre-
sentation in the thalamus and cortex. Among non-eutherian
mammals studied ips projections seem to be insignificant.
In cohorts Unguiculata and Glires ips representation has
been reported but in all cases the ips projections from
the face and mouth seem to be small. Large amounts of ips
representation have been reported in all ferungulates studied
except the horse. In other words the variation in character
of projections to the higher centers of the medial lemniscal
system is consistent and systematic in light of Simpson's
(1945) classification of mammals..

A second hypothesis to account for the variation seen
in this and other studies is that these variations represent
specializations (which are of course evolutionary changes)

at levels lower than the major mammalian groups which

58
Simpson (1945) called cohorts. In other words if more
animals from various groups were examined variations within
groups may prove to be as great as variations between groups.
Only further systematic studies which pay particular atten-
tion to the projections from the face and mouth will resolve

this question.

BIBLIOGRAPHY

BIBLIOGRAPHY

Adrian, E. D. 1943. Afferent areas in the brain of
ungulates. B1312. 66: 89-103.

Baldwin, H. A., S. Frenk, and J. I. Lettvin. 1965.
Glass-coated tungsten micro-electrodes. figlgggg,
148: 1462-1464.

Blomquist, A. J., R. M. Benjamin and R. Emmers. 1962.
Thalamic localisations of afferents from the tongue

in squirrel monkey ( ). Igg,gg§;nal
2!. mm W ~88

Cabral, R. J. and J. I.Johnson. 1971. The organization
of mechanoreceptive rejections in the ventrobasal

thalamu- of sheep. Jamal 91 W
W. 141: 17- .

Clark, W. E. LeGros and Powell, T. P. S. 1953. On the
thalamo-cortical connexions of the general sensory

cfiortexaof_Macaccafl.‘1 :WW 3; m min

Emmers, R. 1965. Organisation of the first and second
somesthetic regions (81 and 811) in the rat thalamus.

1b.: ml 2.1? W W. 124: 215-229

Hubel, D. H. 1957. Tungsten microelectrode for recording
from single units. figigggg, 125: 549-550.

Johnson, J. 1., G. I. Batten, and E. V. Rubel. 1969.
Related specializations of brains and behaviours in
sheep and raccoons. Presented at Second Annual
Winter Conference on Brain Research. Snowmass-as-
Aspen, Colorado.

Lende, R. A. 1964. Representation in the cerebral cortex
of a primitive mammal. Sensorimotor, visual, and
auditory fields in the echidna ( ac cglegtug).

mo na 23W. 27: *4-

Lende R. A. 1970. Cortical localization in the tree shrew
(Tupaia). Brain w. 18: 61—75

Lende, R. A. and K. M. Sadler, 1967. Sensory) and motor

areas in neocortex of hedgehog (3:11:2211.) 21212
gigggggh, 5: 390—405.

59

60

Lende, R. A. and C. N. Voolsey. 1956. Sensory and motor
localization in cerebral cortex of porcupine ( 0

marine) muW. 19: .

Mountcastle, V. B. and E. Henneman. 1949. Pattern of
tactile representation in the thalamus of the cat.

mmW.1zx 35-100.

. 1952. The representation of
tactile sensibil1ty 1n the thalamus of the monkey. II:

m}. at. W W 97: 409-440

Pinto-Hamuy, T. P., R. B. Bromiley, and C. N. Voolsey. 1956.
Somatic afferent areas I and II of dogs cerebral cortex.

isms]. at Wm 19. 485-499.

Pubols, B. H. 1968. Retrograde degeneration study of somatic
sensory thalamocortical connections in brain of Virginia

opossum. ngig,figgggzgh, 7: 232-251.

Pubols, L. M. 1968. Somatic sensory representation in
thalamic ventrobasal complex of spider monkey (Atglgg).

Brain. W- 1' 305-323-

Pubols, B. H. Jr., and L. M. Pubols, 1966. Somatic sensory
representation in thalamic ventorobasal complex of the

Virginia ope-Inl- m M at W We
127: 19-34

Pubols, B. B. Jr., and L. M. Pubols. 1971. Somatotopic
organization of spider monkey somatic sensory cerebral

23:31:}. 111.: Meal 91 W W- 141:

Rose, J. E. and V. B. Mountcastle. 1952. The thalamic
tactile region in the rabbit and cat. Ihg,£gn;n§1,gz,

WW- 97: 441-490.
. 1959. Touch and Kinesthetics.

In Field 3. (Ed. ) W¥§ngbgok Section I
W.V ' e I G‘sfifigton. American '

ysio og1ca eciety. 387-429.

Simpson, G. G. 1945. iiiiiiplga f; Siiggiféfigtion 22d
snug fifi‘ . L '85
O ' - O

Welker, W. I. and J. 1. Johnson. 1965. Correlation between
nuclear morphology and somatotopic organization in
ventrobasal complex of the raccoon thalamus. gournal
21.‘B£1£I¥. (London and Cambridge). 99: 761-

 

61

Woolsey, C. M. 1958. Organization of somatic sensory and
motor areas of the cerebral cortex. In H. F. Harlow

and C. M. Woolsey (Eds.). W m B'
Bases 2;,nggzig;_ Madison, Wisconsin. Un versity

o 1scons1n Press. 63-81.

Woolsey, C. N. and D. Fairman. 1946. Contralateral,
ipsilateral, and bilateral representation of cutaneous
receptors in somatic areas I and II of the cerebral

cortex of pit, sheep, and other mammals. §nzggzx,

Woolsey, D. M. and G. H. vang. 1945. Somatic sensory areas
I and II of the cerebral cortex of the rabbit.

Federation 9; America? §ggigtns f9; W
nglogy. Federation oceedings. 4: 9.

62
General References
Oswaldo-Cruz, E. and C. E. Rocha-Miranda. 1968. 2h;
. . A

g: 21 $ we (11411211:
oar hi 9 t 1 Atlas ;¥,St
s i uto e B10 is ca, n vers1

de Janeior.

 

 

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